I did not write the following instructions or take the pictures. They were taken from The Simple Dollar blog. Visit the site to see a video of the finished product, the cost breakdown, and even pictures showing how well the detergent works.
My personal review: Making the detergent was very easy and fast. When I used it my clothes came out smelling clean, but not like lavender as some of the newer detergents are scented. I have not yet washed any clothing that was stained so I cannot vouch for its stain removing effects. I was very pleased with the detergent and plan to continue using it.
Making the Laundry Detergent
The only ingredients you actually need for homemade laundry detergent are as follows:
1 cup washing soda (I use Arm & Hammer)
1/2 cup borax (I use 20 Mule Team)
1 bar soap (I use whatever’s cheap, in this case Pure & Natural)
Approximately 3 gallons water
You’ll also need a container of some sort to store this in (I use a five gallon bucket with a lid), something to stir it (I use a large wooden spoon), another pot to boil soapy water in (I use the pot in the picture), and something to cut up the soap (I use the box grater in the picture).
First thing, put about four cups of water into the pan and put it on the stove on high until it’s at boiling, then lower the heat until it’s simmering.
While it’s heating up, take a bar of soap and cut it up into little bits. I found a lot of success using our box grater, which resulted in a ton of little soap curls.
When the water is boiling, start throwing in the soap. I recommend just doing a bit at a time, then stirring it until it’s dissolved. Here, I made the mistake of just tossing in all of the soap at once, which wasn't particularly helpful:
Stir the soapy water with a spoon until all of the soap is dissolved. Eventually, the water will take on the color of the soap you added, albeit paler. I used Pure & Natural soap for this, which was a white soap that looked a lot like a bar of Ivory.
In the end, you’ll have some very warm soap soup:
To this bucket add a cup of the washing soda and the soap solution you made and stir. The borax is optional - some people say that it’s too harsh, but I’ve always found that it did a good job getting clothes clean and fresh smelling, so I recommend adding a half cup of borax to the mix.
After stirring, you’ll have a bucket full of vaguely soapy water:
Don’t worry if your batch doesn’t match the color of my own - it varies depending on what kind of soap you use. I made a batch with Lever 2000 in the past and it had a greenish tint to it, and I’ve heard reports of all kinds of different colors from other people who have tried this.
At this point, let the soap sit for 24 hours, preferably with a lid on it. I just took our bucket to the laundry room.
When you take off the lid, you’ll find any number of things, depending on the type of soap you used and the water you used. It might be firm, like Jello; it might be very watery; it might even be like liquid laundry detergent. Just stir it up a bit and it’s ready to be used.